Rodents of the genus Cerradomys belong to tribe Oryzomyini, one of the most diverse and speciose groups in Sigmodontinae (Rodentia, Cricetidae). The speciation process in Cerradomys is associated with chromosomal rearrangements and biogeographic dynamics in South America during the Pleistocene era. As the morphological, molecular and karyotypic aspects of Myomorpha rodents do not evolve at the same rate, we strategically employed karyotypic characters for the construction of chromosomal phylogeny to investigate whether phylogenetic relationships using chromosomal data corroborate the radiation of Cerradomys taxa recovered by molecular phylogeny. Comparative chromosome painting using Hylaeamys megacephalus (HME) whole chromosome probes in C. langguthi (CLA), Cerradomys scotii (CSC), C. subflavus (CSU) and C. vivoi (CVI) shows that karyotypic variability is due to 16 fusion events, 2 fission events, 10 pericentric inversions and 1 centromeric repositioning, plus amplification of constitutive heterochromatin in the short arms of the X chromosomes of CSC and CLA. The chromosomal phylogeny obtained by Maximum Parsimony analysis retrieved Cerradomys as a monophyletic group with 97% support (bootstrap), with CSC as the sister to the other species, followed by a ramification into two clades (69% of branch support), the first comprising CLA and the other branch including CVI and CSU. We integrated the chromosome painting analysis of Eumuroida rodents investigated by HME and Mus musculus (MMU) probes and identified several syntenic blocks shared among representatives of Cricetidae and Muridae. The Cerradomys genus underwent an extensive karyotypic evolutionary process, with multiple rearrangements that shaped extant karyotypes. The chromosomal phylogeny corroborates the phylogenetic relationships proposed by molecular analysis and indicates that karyotypic diversity is associated with species radiation. Three syntenic blocks were identified as part of the ancestral Eumuroida karyotype (AEK): MMU 7/19 (AEK 1), MMU 14 (AEK 10) and MMU 12 (AEK 11). Besides, MMU 5/10 (HME 18/2/24) and MMU 8/13 (HME 22/5/11) should be considered as signatures for Cricetidae, while MMU 5/9/14, 5/7/19, 5 and 8/17 for Sigmodontinae.

Cerradomys属的啮齿动物属于 Oryzomyini 部落，是 Sigmodontinae（啮齿目、仓鼠科）中最多样化和最多样化的类群之一。角鼠的物种形成过程与更新世时期南美洲的染色体重排和生物地理动态有关。由于Myomorpha啮齿动物的形态、分子和核型方面的进化速度不同，我们策略性地利用核型特征来构建染色体系统发育，以研究使用染色体数据的系统发育关系是否证实了通过分子系统发育恢复的Cerradomys类群的辐射。使用大头龟(HME) 全染色体探针对C. langguthi (CLA) 、Cerradomys scotii (CSC)、 C. subflavus (CSU) 和C. vivoi (CVI) 进行比较染色体涂色，结果表明核型变异是由于 16 个融合事件造成的， 2 次裂变事件、10 次中心周倒位和 1 次着丝粒重新定位，以及 CSC 和 CLA X 染色体短臂中组成型异染色质的扩增。通过最大简约分析获得的染色体系统发育将Cerradomys检索为单系类群，支持率 97%（引导程序），CSC 作为其他物种的姐妹，随后分支为两个分支（分支支持率 69%），第一个分支包括CLA 和其他分支包括 CVI 和 CSU。我们整合了由 HME 和小家鼠(MMU) 探针研究的真鼠类啮齿动物的染色体涂色分析，并鉴定了仓鼠科和鼠科代表之间共享的几个同线块。 Cerradomys属经历了广泛的核型进化过程，多次重排塑造了现存的核型。染色体系统发育证实了分子分析提出的系统发育关系，并表明核型多样性与物种辐射有关。三个同线性块被鉴定为祖先 Eumuroida 核型 (AEK) 的一部分：MMU 7/19 (AEK 1)、MMU 14 (AEK 10) 和 MMU 12 (AEK 11)。此外，MMU 5/10 (HME 18/2/24) 和 MMU 8/13 (HME 22/5/11) 应被视为仓鼠科的特征，而 MMU 5/9/14、5/7/19、5和 8/17 对于 Sigmodontinae。